How to Set 'Semi-Bold' Font via CSS? Font-Weight of 600 Doesn't Make It Look Like the Semi-Bold I See in My Photoshop File

How do I set 'semi-bold' font via CSS? Font-weight of 600 doesn't make it look like the semi-bold I see in my Photoshop file

The practical way is setting font-family to a value that is the specific name of the semibold version, such as

font-family: "Myriad pro Semibold"

if that’s the name. (Personally I use my own font listing tool, which runs on Internet Explorer only to see the fonts in my system by names as usable in CSS.)

In this approach, font-weight is not needed (and probably better not set).

Web browsers have been poor at implementing font weights by the book: they largely cannot find the specific weight version, except bold. The workaround is to include the information in the font family name, even though this is not how things are supposed to work.

Testing with Segoe UI, which often exists in different font weight versions on Windows systems, I was able to make Internet Explorer 9 select the proper version when using the logical approach (of using the font family name Segoe UI and different font-weight values), but it failed on Firefox 9 and Chrome 16 (only normal and bold work). On all of these browsers, for example, setting font-family: Segoe UI Light works OK.

Safari on iOS unable to show a normal CSS font as bold

Safari won't display a font out of its available font-weights.

So if that font doesn't have bold type then it won't be bold in safari.

CSS font-weight numbers: how do they work?

The details of how numeric values are mapped to font weights are covered in the spec which states:

The values '100' to '900' form an ordered sequence, where each number
indicates a weight that is at least as dark as its predecessor. The
keyword 'normal' is synonymous with '400', and 'bold' is synonymous
with '700'. Keywords other than 'normal' and 'bold' have been shown to
be often confused with font names and a numerical scale was therefore
chosen for the 9-value list.

'599' is not a valid value for the font-weight property

Black font is not really black

When importing fonts from Google Fonts, you can customize the options you want. Some fonts will have different options. In your case, here is a screenshot of how that "customize" page looks like:

Sample Image

By doing that, your import snippet will be different when you go back to the "Embed" tab. To include the 900 weight, you should import the font like this:

<link href="https://fonts.googleapis.com/css?family=Montserrat:400,900&display=swap" rel="stylesheet">

For the second question

"Is there a way to easily select Black, Thin, Thin Italic, Semibold etc. into CSS ?"

by adding the correspondent options in the Google Fonts, you could also set your css with font-weight: bold or font-weight: bolder or font-weight: lighter...

See this link for the full reference:

https://developer.mozilla.org/en-US/docs/Web/CSS/font-weight

Font-weight values not working

If you want to use a different type of font weight, it is important that your font supports this weight type.

If the font doesn't have a 500 or 600 type, it is not possible to use this font weight. The browser will automatically pick the closest value to the font that is available. In this case 600 will change in the 700 which is supported

How to add multiple font files for the same font?

The solution seems to be to add multiple @font-face rules, for example:

@font-face {
    font-family: "DejaVu Sans";
    src: url("fonts/DejaVuSans.ttf");
}
@font-face {
    font-family: "DejaVu Sans";
    src: url("fonts/DejaVuSans-Bold.ttf");
    font-weight: bold;
}
@font-face {
    font-family: "DejaVu Sans";
    src: url("fonts/DejaVuSans-Oblique.ttf");
    font-style: italic, oblique;
}
@font-face {
    font-family: "DejaVu Sans";
    src: url("fonts/DejaVuSans-BoldOblique.ttf");
    font-weight: bold;
    font-style: italic, oblique;
}

By the way, it would seem Google Chrome doesn't know about the format("ttf") argument, so you might want to skip that.

(This answer was correct for the CSS 2 specification. CSS3 only allows for one font-style rather than a comma-separated list.)